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Achieving accurate FTIR measurements on high performance bandpass filters
The sources of ordinate error in FTIR spectrometers are reviewed with reference to measuring small out-of-band features in the spectra of bandpass filters. Procedures for identifying instrumental artefacts are described. It is shown that features well below 0.01%T can be measured reliably
Radiocarbon measurement program at the centro nacional de aceleradores (CNA), Spain
In September 2005, an accelerator mass spectrometry (AMS) system based on a 1MV Tandetron accelerator
arrived at the Centro Nacional de Aceleradores (CNA). One of the main research programs for this AMS facility is based on
radiocarbon. At the same time as the AMS facility was installed and tested, the 14C sample preparation laboratory was
designed and set up. A graphitization line that allows the preparation of 5 samples in parallel was designed and built in October
2006. The first months were mainly dedicated to check and optimize all the sample processing. For such a task, several
reference samples have been prepared and measured. Since the beginning of 2007, the laboratory has been fully operational
and is currently performing as a service for the scientific community. During 2007, nearly 100 unknown samples were prepared
and measured in our AMS system. Most of them were for dating purposes, but also other applications were investigated.
The performance of the 14C laboratory and dating service will be shown, with some examples as illustration
Stereotaxic cutting of post-mortem human brains for neuroanatomical studies
Stereotaxis is widely used in clinical neurosurgery, neuroradiosurgery, and neuroimaging. Yet, maps of brain structures obtained from post-mortem human brains are not usually presented in known stereotaxic coordinates. Post-mortem brain data given in stereotaxic coordinates would facilitate comparisons with in vivo human neuroimages and would also facilitate intra and inter-experiment comparisons. In this article, we present a crafted instrument for stereotaxic cutting of post-mortem human brain hemispheres. The instrument consists of a transparent methacrylate plate facing a mirror, four legs, and lateral regularly spaced columns permitting the insertion of large knives in-between the columns. This instrument can be built in any laboratory to obtain human brain slabs in the stereotaxic space of Talairach and Tournoux. We explain in detail the procedure for stereotaxic cutting of human brain hemispheres in the coronal plane, as well as the basis for calculating stereotaxic coordinates of histological sections obtained following the stereotaxic cutting protoco
Mapping the primate thalamus: systematic approach to analyze the distribution of subcortical neuromodulatory afferents
Neuromodulatory afferents to thalamic nuclei are key for information transmission and thus play critical roles in sensory, motor, and limbic processes. Over the course of the last decades, diverse attempts have been made to map and describe subcortical neuromodulatory afferents to the primate thalamus, including axons using acetylcholine, serotonin, dopamine, noradrenaline, adrenaline, and histamine. Our group has been actively involved in this endeavor. The published descriptions on neuromodulatory afferents to the primate thalamus have been made in different laboratories and are not fully comparable due to methodological divergences (for example, fixation procedures, planes of cutting, techniques used to detect the afferents, different criteria for identification of thalamic nuclei…). Such variation affects the results obtained. Therefore, systematic methodological and analytical approaches are much needed. The present article proposes reproducible methodological and terminological frameworks for primate thalamic mapping. We suggest the use of standard stereotaxic planes to produce and present maps of the primate thalamus, as well as the use of the Anglo-American school terminology (vs. the German school terminology) for identification of thalamic nuclei. Finally, a public repository of the data collected under agreed-on frameworks would be a useful tool for looking up and comparing data on the structure and connections of primate thalamic nuclei. Important and agreed-on efforts are required to create, manage, and fund a unified and homogeneous resource of data on the primate thalamus. Likewise, a firm commitment of the institutions to preserve experimental brain material is much needed because neuroscience work with non-human primates is becoming increasingly rare, making earlier material still more valuableOpen Access funding provided thanks to the CRUE-CSIC
agreement with Springer Nature. CC and IP-S were the recipients of
grants from Chair in Neuroscience UAM-Fundación Tatiana Pérez
de Guzmán el Bueno, Spain. MAG-C was the recipient of a Beatriz
Galindo senior research position in the School of Medicine, Universidad Autónoma de Madrid (BEAGAL18/00098) and of a Grant for
I+D Projects to the Beatriz Galindo Program Researchers at Universidad Autónoma de Madrid (SI2/PBG/2020–00014) from the Madrid
Government (Comunidad de Madrid-Spain) under the Multiannual
Agreement with Universidad Autónoma de Madrid in the line of action
encouraging young research doctors, in the context of the V PRICIT
(Regional Programme of Research and Technological Innovation
The epic of the thalamus in anatomical language
Understanding the origin of Greek and Latin words used as metaphors to label brain
structures gives a unique window into how scientific and medical knowledge was
produced, preserved, and transmitted through generations. The history of the term
thalamus exemplifies the complex historical process that led to the current anatomical
terminology. From its first mention by Galen of Pergamon in the 2nd century A.D. to
its definitive and current use by Thomas Willis in 1664, the thalamus had an epical
journey through 1500 years across Europe, the Middle East, and the North of Africa.
The thalamus was confusingly described by Galen, in the Greek language, as a chamber
to the brain ventricles. The term thalamus was transferred from Greek to Syriac through
the translations of Galen’s books done in Baghdad and also from Syriac to Arabic. Then,
it was translated in Europe during the Middle Ages from the Arabic versions of Galen’s
books to Latin. Later, during the Early Renaissance, it was translated again to Latin
directly from the Greek versions of Galen’s books. Along this epical journey through
languages, the term thalamus switched from referring to a hollow structure connected to
brain ventricles to naming a solid structure at the rostral end of the brainstem. Finally, the
thalamus was translated from Latin to modern languages, where it is used, until today,
to name a nuclear complex of subcortical gray matter in the lateral walls of the third
ventricl
Mapping the primate thalamus: historical perspective and modern approaches for defining nuclei
The primate thalamus has been subdivided into multiple nuclei and nuclear groups based on cytoarchitectonic, myeloarchitectonic, connectional, histochemical, and genoarchitectonic differences. Regarding parcellation and terminology, two main schools prevailed in the twentieth century: the German and the Anglo-American Schools, which proposed rather different schemes. The German parcellation and terminology has been mostly used for the human thalamus in neurosurgery atlases; the Anglo-American parcellation and terminology is the most used in experimental research on the primate thalamus. In this article, we review the historical development of terminological and parcellation schemes for the primate thalamus over the last 200 years. We trace the technological innovations and conceptual advances in thalamic research that underlie each parcellation, from the use of magnifying lenses to contemporary genoarchitectonic stains during ontogeny. We also discuss the advantages, disadvantages, and practical use of each parcellationCC and IP-S were the recipients of grants from Chair in
Neuroscience UAM-Fundación Tatiana Pérez de Guzmán el Bueno,
Spain. MAG-C was the recipient of a Beatriz Galindo senior research
position in the School of Medicine, Universidad Autónoma de Madrid
(BEAGAL18/00098) and of a Grant for I + D Projects for the Beatriz
Galindo Program Researchers at Universidad Autónoma de Madrid
(SI2/PBG/2020-00014) from the Madrid Government (Comunidad de
Madrid-Spain) under the Multiannual Agreement with Universidad
Autónoma de Madrid in the line of action encouraging youth research
doctors, in the context of the V PRICIT (Regional Programme of
Research and Technological Innovation
Revitalización del espacio urbano como escenario para la integración social de la población de San Juan de Lurigancho
Esta investigación se realizó con el objetivo de Determinar si la revitalización del
espacio urbano favorece la integración social de los pobladores de San Juan de
Lurigancho, La revitalización del espacio urbano evidencia la condición en la que
se encuentra la ciudad en el entorno urbano, busca revertir los daños causados por
los efectos sociales, fiscos y económicos, este proceso desarrolla la transformación
de la imagen urbana a través de sus lineamentos estratégicos con la finalidad de
recuperar el espacio deteriorado convirtiéndolo en un espacio óptimo para las
personas mejorando la calidad de vida. Por otro lado, dentro de las teorías de
Howar hace referencia a la integración social, mencionando que son grupos de
personas que articulan un espacio, en cual se relacionan y realizan diferentes
actividades sociales para su desarrollo económico, social y cultural en la sociedad
es `por ello que para realizar esta acción social se requiere de espacios
confortables y habitables. Esta investigación tiene como carácter de medición el
enfoque cualitativo con un diseño fenomenológico con un alcance descriptivo el
cual nos ayudara a explicar y describir los hechos desde una percepción distinta.
Por otro lado, la validez de mis instrumentos se realizó mediante un juicio de
expertos los cuales fueron de grado académico de Magister, para la recolección de
datos de nuestra investigación se realizaron fichas de análisis documental y
entrevistas semi estructuradas a 3 arquitectos y 1 poblador de la zona los cuales
aportaron significativamente en nuestra investigación, se conoció las opiniones de
los expertos los cuales nos brindaron información relevante de nuestro tema y el
poblador nos dio a conocer una perspectiva más realista de las condiciones en que
se encuentra y lo que desea a futuro. Es por ello, que nuestra investigación
describirá como se puede mejorar la calidad de vida de las personas mediante la
revitalización urban
Influencia de la obesidad sobre los marcadores de metabolismo óseo y el riesgo de fractura
La osteoporosis se define como una enfermedad esquelética progresiva
sistémica, caracterizada por baja masa ósea y un aumento de la fragilidad, que condiciona
un aumento del riesgo de fractura. Por otro lado, la obesidad, supone la enfermedad
metabólica más prevalente del mundo desarrollado. La relación entre obesidad y
metabolismo óseo es controvertida, ya que, en las últimas décadas se ha puesto en duda el
papel protector de la obesidad sobre el desarrollo de la osteoporosis debido a que sobre el
hueso influyen gran cantidad de factores mecánicos, hormonales e inflamatorios.
Nuestro objetivo es 1) Evaluar las diferencias en los parámetros bioquímicos de metabolismo óseo
entre mujeres postmenopáusicas con y sin obesidad. 2) Comparar el riesgo de fractura a
cinco años entre mujeres postmenopáusicas con y sin obesidad.
Se diseñó un estudio de tipo observacional prospectivo
longitudinal de cohortes de mujeres postmenopáusicas con obesidad (IMC (Índice de Masa
Corporal)>30kg/m2)) y sin obesidad (IMC<30kg/m2). Se incluyeron en el estudio 250
pacientes, de las cuales 124 eran mujeres postmenopáusicas sin obesidad pertenecientes
al área Oeste de Valladolid y 126 mujeres con obesidad delárea Este de salud. Se analizaron
un grupo de variables de tipo epidemiológico, bioquímico (-CrossLaps, péptido
aminoterminal del procolágeno tipo I (P1NP)); 25OH Vitamina D y hormona paratiroidea
(PTH), antropométrico y datos de fractura a los 5 años del estudio inicial (desde 2014 a
2019).
Se observó que las mujeres con obesidad mostraron niveles más bajos de
Vitamina D (O: Obesidad :17,27 (7,85), NoO: 24,51 (9,60); p<0,01) junto con un aumento de
PTH (O: 53,24 (38,44-65,96), NoO: 35,24 (25,36-42,40); p<0,01). El marcador de formación
ósea (P1NP) se encontró elevado en mujeres sin obesidad, aunque, siendo únicamente
significativo en las mujeres con edades menores de 53 hasta los 56 años (<53 años: O:46,11
(29,91-55,81), NoO: 65,49 (50,64-85,55); p<0,01; y de 53 a 56 años: O: 43,40 (32,86-46,40),
NoO: 56,04 (44,78-70,01); p<0,01). El marcador de resorción ósea (-CrossLaps) se
encontró aumentado en mujeres con obesidad siendo significativo en mayores de 59 años
(O: 0,39 (0,14), NoO: 0,24 (0,09); p<0,05). Se realizó un análisis de regresión lineal en el que
se encontró una relación inversa entre el IMC y la Vitamina D (<53 años: R=-0,33; p≤0,01)
y entre el marcador de formación ósea P1NP y el IMC (<53 años: R=-0,37; p≤ 0,01). Se
obtuvo una relación positiva entre los niveles de PTH y el IMC (<53 años: R=0,55; p≤ 0,01).
No se observaron diferencias en el riesgo de fractura a 5 años en función del IMC.
Las diferencias en el metabolismo óseo fueron un descenso de formación
ósea (P1NP) a edades más tempranas y un aumento de resorción ósea (-crosslaps) en las
mujeres con obesidad mayores de 59 años. Las mujeres con obesidad presentaron niveles
inferiores de Vitamina D independientemente de la edad junto con aumento o de la PTH. La
obesidad no supuso un incremento en el riesgo de fractura a 5 años.Grado en Medicin
A study of the Suess effect using a raised peat bog as historical archive
The radiocarbon content in a peat core from Gävle, Sweden, 61.0 oN, 17.0 oE, has been studied. This is a raised peat bog which only receives material from atmospheric deposition. There has been an increased use of fossil fuels by industries and also locally by transports and heating of domestic buildings. There has been fallout of 14C from nuclear tests during the 1950ies and 1960ies and also from the Chernobyl accident in 1986. There is also emission of 14C from nuclear facilities. The 14C/12C ratio from the Chernobyl accident is unclear since it was a graphite moderated reactor and the graphite was burning. The core was sampled in 2008 and was previously dated using the 210Pb method, giving a growth rate of 0.15 mm/yr. The top 21 cm have been analyzed to obtain radiocarbon content by Accelerator Mass Spectrometry (AMS) at the Centro Nacional de Aceleradores (CNA), Seville Spain. Using 0.5 cm samples, information about the last 140 years could be obtained with resolution better than 4 years. Results show a clear depletion of F14C levels in the area, the so called SUESS effect with maximum levels of only F14C=1.2333±0.0043, and the absence of a clear nuclear tests peak
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